DE102011089331A1 - Adhesive tape system for forming a tear strip - Google Patents

Abstract

The invention relates to an adhesive tape system, in particular for opening cardboard boxes, consisting of an adhesive tape A equipped with an adhesive coating on at least one side with a carrier, wherein the carrier comprises a film and filaments extending in the longitudinal direction of the carrier, and an adhesive tape B equipped with an adhesive coating on at least one side with a film carrier, wherein the adhesive tapes A and B are arranged one above the other.

Description

The invention relates to an adhesive tape system for forming a tear strip.

Tear strips are known and serve in various forms as an opening aid on the one hand for cigarette packs, confectionery packaging and similar packaging, which are wrapped with a film, on the other hand for cardboard such as detergent packaging. In this case, the tear strip is attached to the package so that you pull to open on the tear strip and thus separates the wrapping film or the cardboard at the desired location.

Traditionally tear strips are in use, which are equipped on one side with a hotmelt-based adhesive. For example, these are in the US 3,187,982 A , of the US 3,311,032 A or the CA 749 198 A described.

Furthermore, a tear strip is used which is self-adhesive. For this purpose, one uses a monoaxially stretched carrier film, which is equipped with a self-adhesive layer on one side and a silicone release layer on the other side. Optionally, under one of the two layers is a print. Such or similar structures are known for the production of pressure-sensitive adhesive tapes, for example from DE 21 04 817 A , of the US 3,088,848 A , of the US 3,482,683 A or the US 2,956,904 A , Not disclosed in these documents is the use of such film structures for self-adhesive tear strips. The use of self-adhesive tapes of this kind as a tear strip but is in the journal "Packaging Review" of February 1973, page 57 mentioned.

A special embodiment of these self-adhesive tear strips describes the DE 43 38 524 A1 , In this a self-adhesive tear strip is disclosed consisting of a carrier film, a release layer, an adhesive layer facing away from the release layer and optionally a pressure under the adhesive or release layer. The strip is characterized in that the carrier film consists of a stretched film, that the release and adhesive layer of aqueous solution, emulsion or dispersion are applied and that release layer, ink and adhesive layer on a relation to the tear strip to a much wider film in one operation be applied on a machine.

Usual for use as an opening aid of film packaging are at least monoaxially, preferably biaxially stretched at least single-layer 15 to 60 microns thick carrier films.

Self-adhesive or heat-activatable tear strips of longitudinally stretched polypropylene film are used for the tearing of cardboard boxes for a long time. They are available in foil thicknesses of 50 to 140 μm. Film thicknesses greater than 85 μm are used when opening particularly heavy cardboard. More common are tear strips in thicknesses between 60 and 90 microns.

Tear tabs based on a monoaxially stretched polypropylene backing often use a special polymer blend optimized for tearing performance, resulting in tensile strengths in the longitudinal direction of from 230 to 330 N / mm ² .

These polypropylene tear strips, preferably in the range of 60 to 65 μm, exhibit perfect tear-open behavior in all corrugated paperboard cartons, including microwell paperboard. This applies regardless of whether it is torn open exactly in the direction of the glued strip.

"Just in the direction of the glued-on strip" means that the tear strip is guided during the tearing process so that the direction of pull never deviates from the direction specified by the tear strip glued to the back of the cardboard and also becomes visible as a tear-open during the tearing process from the front side of the cardboard , Only then is the distribution of forces in the tear strip during the tearing process symmetrical and the load on both edges uniform. In practice, this ideal tear direction is usually not respected. It is to be expected deviations from this direction up to about 30 °.

A trend in the tear tape market is the departure from the film recipe optimized for the tearing performance. A reduced Aufreißleistung here is accepted accepting in order to achieve in return improved machinability of the tear strip during its application.

For example, a reduction in the toughening additives can be made below the amount recommended for optimal tearing performance, until completely eliminated.

Heavy full-board grades of about 1000 g / m ² can only be torn open in the optimum direction of tear. When deviating from this direction, tearing may occur during the tearing operation due to the asymmetrical loading of the strip from the more heavily loaded edge of the strip. The frequency of the breaks is influenced, for example, by inhomogeneities in the film, by micro-slits in the cut edges of the film strips, by wood particles or by particularly solidified particles in the cardboard and similar phenomena. In addition, the tearing speed has an influence.

For the packaging of detergents, full board between 450 and 600 g / m ² basis weight are used to a greater extent, which may have a wax-impregnated intermediate layer, but in any case with a laminated top layer of high gloss cast chromolux papers are provided. These boards can be torn open with the polypropylene tear strips only with a similar poor result as the above-mentioned 1000 g / m ² -pollpappen.

From the EP 0 269 967 A1 there is known a tear strip having a backing stretched in a predominantly direction provided with an adhesive layer, the backing consisting of at least one base layer provided with at least one tough layer which is tougher than the base layer.

Particularly preferred is a tear strip having a carrier stretched in a predominantly one direction and provided with an adhesive layer, wherein the carrier consists of at least one base layer containing a polypropylene-olefin copolymer and / or a polypropylene toughening additive mixture containing at least one polypropylene-containing tough layer which contains an impact additive and is tougher than the base layer.

In the case of polypropylene-based tear strips, preference is given to using TPP (corresponding to monoaxially stretched polypropylene (MOPP)), since only slight elongation may occur under high tensile load.

High tensile loads occur once in the end use, when the tear strip is pulled when opening the package by the cardboard or the cardboard or the film and this is sure to cut. They also occur in the application of the tear strip on the packaging, as it is often applied at speeds of more than 150 m / min. In particular, at the start, that is the laying of the tear strip on, for example, the cardboard, the coil up to about 15 kg heavy, to which the tear strip is made up commercially available, suddenly and suddenly accelerated. Even in continuous operation tensile stresses of more than 8 N often act on the tear strip. This excludes the use of unstretched or even biaxially oriented polypropylene.

When TPP is used without release, when unrolling, ie when separating mass and carrier, a splicing of the carrier occurs, that is, a part of the longitudinally oriented and stretched fibers is torn out of the carrier surface. This can interfere with the process of packaging if the coated film web, which is much wider than the tear strip, is cut into individual tear strips and unwound from the bale for this purpose. The fibers standing out of the carrier surface themselves hinder the process, or the entire carrier web can also be torn off. Furthermore, similar problems may occur when unrolling the tear strip during application to the package.

Currently, sales trays, which serve to accommodate products packed in individual boxes, fulfill two tasks. On the one hand, the boxes are arranged in an open-topped tray. This tray is presented visually appealing to the customer in the shop, which can remove individual boxes from the tray. The tray ensures that the boxes are bundled and always remain in an orderly position.

On the other hand, the trays are to protect the boxes in the tray on the way from the producer or bottler to the store. For this purpose, the product is completely surrounded with a cardboard packaging, which is torn open for the presentation of the content using a tear strip. The upper part of the box is removed, the lower part serves as a sales tray.

To create a visually pleasing impression, it is necessary for the tear line to have a clean and smooth edge finish. The cardboard of the box should not fray, furthermore the crack must run as precisely as possible straight ahead. The expert speaks in this context of a "clean cut".

To open cardboard boxes so that a clean cut is created, there are mainly two solutions.

The so-called Adalissystem (developed by the company Adalis) consists of two adhesive tapes (guide tape = band A and tear strips = band B), which, as in 1 shown, are installed in the box. The carton is composed of an inner liner and an outer liner with a paperboard shaft as usual between the liners.

The tapes consist of a carrier material made of numerous polyester filaments, which are held together with an adhesive. The carrier material is coated with a hot melt adhesive. The two liners and the shaft and the two tapes run through a heating channel, so that according to the 1 a laminate is created.

Disadvantage of this system is that the tapes used are very thick (2 × 200 to 250 microns) and thereby deteriorates the printed image on the outer visible liner by wear of the raised points during transport and storage. In addition, many of these unfolded cartons (carton blanks) and folded boxes are stacked as part of a production. Since the tapes are always applied to the same place on the carton blank, this results in the buildup of thickness in the stack at this point. This will cause the stack to skew, and the sheets will start to slip at a certain grade, resulting in unstable stacks. Furthermore, due to the high thickness, the number of running meters of adhesive tape with the same width and same coil dimensions on an adhesive tape reel is significantly lower than with thinner tapes. For the corrugated packaging industry, however, it is often necessary to run larger production campaigns, which means that the coil-changing equipment either has to be stopped or spliced while the system is running, which always involves a high risk of cracking.

Furthermore, problems can arise when printing such cartons, because different pressure ratios result from the different thicknesses of the printing substrate in the printing process, which can result in an uneven print image. Therefore, it is of interest to the fabricator of corrugated sheets with tear strips to use thin tapes first and foremost to avoid such problems.

A variant consists of scratching the cardboard provided with the tear strip in the region above the outer edges of the tear strip, ie weakening it (so-called "liner slitting"). This shows the 2 , For this case, resort to a tear strip, for example, has only a thickness of 90 microns, which largely avoids the problems outlined above.

The outer liner is previously scored along the desired crack edge on the surface, so that it leaves a clean crack edge when opening and results in a visually appealing display after opening. Disadvantage of this solution is that the injury of the outer liner leads to loss of stability in the z direction of the carton. The cardboard preferably gives way at the injured site. This phenomenon is measured with the so-called "box compression test".

This solution thus has the consequence that the stackability of the unfolded cartons is reduced.

The object of the invention is to achieve over the prior art, a significant improvement and to provide a solution with which a cardboard can be torn, resulting in clean crack edges in the carton and the solution should thicken the cardboard as little as possible.

This object is achieved by an adhesive tape system, as characterized in more detail in the main claim. Advantageous embodiments of the invention are described in the subclaims. Furthermore, uses of the adhesive tape system according to the invention and a cardboard equipped with the adhesive tape system are encompassed by the inventive concept.

Accordingly, the invention relates to an adhesive tape system, in particular for opening cardboard boxes, consisting of an at least one side with an adhesive coating equipped adhesive tape A with a carrier, wherein the carrier has a film and extending in the longitudinal direction of the carrier filaments, and at least one side equipped with an adhesive coating adhesive tape B with a film carrier, wherein the adhesive tapes A and B are arranged one above the other.

For the purposes of this invention, a filament is understood to mean a bundle of parallel, straight individual fibers / individual filaments. In the literature, these are often referred to as multifilament. Possibly If this fiber bundle can be solidified by twisting, then one speaks of spun or twisted filaments. Alternatively, the fiber bundle can be solidified by swirling with compressed air or water jet. In the following, for the sake of generality, only the term filament is used for all these embodiments.

The filament can be textured or smooth and point-solidified or unconsolidated.

The filaments may consist of organic or inorganic materials, for example and preferably of glass, carbon (carbon), combinations of both types of fibers, aramid fibers, polyamide, drawn polymer fibers such as polyester fibers (such as polyethylene terephthalate), polypropylene fibers, polyethylene fibers, Furthermore, the filaments may be at least partially colored in order to make the carrier more visually appealing. Dyed glass or polymer threads are particularly suitable for this purpose.

The individual filaments then preferably consist of high-strength fibers with a low elongation at break.

Furthermore, mixtures of different filaments are possible.

The number of applied or incorporated filaments depends primarily on the intended use and the intended maximum tensile strength and tensile strength elongation of the carrier and thus the adhesive tape, its own nature and the respective strength of the filaments themselves and can therefore vary within relatively wide limits.

The filaments are preferably continuous filaments. In an advantageous embodiment, all filaments are endless filaments.

The diameters of the filaments are in particular below 60 μm, more preferably between 20 and 45 μm.

The titer of the filaments is preferably more than 10 tex, more preferably more than 50 tex. Furthermore, it has proved to be advantageous if the titer is at most 300 tex, preferably at most 200 tex, more preferably at most 150 tex, further more at most 100 tex.

In a preferred embodiment, there are between 1 and 30 filaments per centimeter width in the carrier material, in particular between 1 and 5, more particularly between 1 and 3, wherein the filaments are more preferably evenly distributed over the width of the film.

Advantageously, the number of filaments is at least 3. In further advantageous variants are present between 3 and 30, more preferably between 3 and 20, most preferably between 3 and 10 filaments.

Furthermore, it has proved to be advantageous if the filaments are arranged regularly in a position aligned parallel to the carrier material or at most in three parallel to the carrier material aligned layers.

In each case, the filaments are arranged parallel to one another in one layer.

Example is on the DE 10 2006 023 935 A1 in which such a filament adhesive tape is disclosed.

The filaments should be firmly attached to the film. This can be done by direct incorporation or admission of the filaments in the film, for example by embedding or by insertion in the production process of the film.

But the filaments can also be subsequently connected to the film, for example, be called welding or lamination, optionally with a corresponding compound layer.

If the carrier is reinforced only by longitudinally integrated filaments, it is called monofilament adhesive tapes.

According to a further advantageous embodiment, the carrier in addition to the longitudinal direction (machine direction) extending filaments in addition to such filaments, which extend in a particularly preferred embodiment in the transverse direction and / or in oblique direction. These filaments can be curved, spiral or zigzag or random.

It is clear to the person skilled in the art that the titer of the filaments must not be too high. These should still be tearable, especially by hand, of course.

In an advantageous development of the subject invention, the carrier is reinforced by an open Filamentgelege or an open filament fabric. In this case, it is called cross-filament tape.

The support in this case consists of a film on which there is a filament structure or fabric on the underside, which is either applied directly to the film or is connected to the film by means of a laminating adhesive.

The adhesive is applied to the side of the film on which the filament scrim or fabric is located.

Further preferably, the filament or fabric has a tensile strength in the machine direction of at least 50 N / cm and an elongation at break of less than 20%, preferably less than 15%, more preferably less than 10%.

According to a further advantageous embodiment, the filament fabric or fabric is a warp knit fabric with weft threads (weft inserted warp knit). Such is for example in the EP 1 818 437 A1 described.

The filament web or web has a machine direction tensile strength of preferably at least 100 N / cm, more preferably 200 N / cm, most preferably 500 N / cm.

Preferably, the filaments used to form the fabric or fabric have a thickness of 2 and 8 dtex, preferably between 4 and 8 dtex, most preferably 5 dtex.

The scrim / tissue can be subsequently dyed or consist of spun-dyed filaments.

According to a further advantageous embodiment of the invention, the filament count in the warp direction is at least 4 / cm, preferably 6 to 10 / cm, more preferably 7 / cm and / or the filament count in the weft at least 1 to 10 / cm, preferably 2 / cm.

The lamination adhesive which may be present may be chosen from the same adhesive systems as will be described in detail later.

In the 9 is shown in the lateral section of the tape, which consists of a carrier 11 consists of on the one side a layer of a self-adhesive coating 12 is applied.

On a 35 μm thick PET film 113 is a WIWK (warp inserted warp knit) fabric made of PET (Diolen) 114 laminated, using a laminating adhesive 115 ,

In the 11 is in the lateral section of an adhesive tape 9 shown that from a carrier 11 consists, on both sides of a layer of a self-adhesive coating 12 . 12a is applied.

In contrast to the carrier of the adhesive tape from the 9 is used as a carrier here only a WIWK (warp inserted warp knit) fabric made of PET (Diolen). A PET film is not present, but can also be provided according to the invention.

In an alternative embodiment, the support consists of a film and a binder layer, which is arranged between the film of the carrier and the adhesive layer, wherein in the binder layer untwisted and ungetgelte single filaments are embedded in the longitudinal direction, which are completely enclosed by the binder layer.

The individual filaments are preferably endless filaments. In an advantageous embodiment, all single filaments are endless filaments.

The individual filaments ideally lie in close-packed spheres, so that there are no gaps or hardly any gaps between the individual filaments encased in the binder. In a preferred embodiment, there are between 400 and 800 individual filaments per centimeter width in the support material, more preferably between 500 and 600, most preferably 550.

Furthermore, it has proven advantageous if the individual filaments are regularly arranged in a position parallel to the film or at most in three layers oriented parallel to the film, specifically if the individual filaments have a fineness of 4 to 8 dtex.

In each case, the individual filaments are arranged parallel to one another in one layer. In another advantageous embodiment, the individual filaments are arranged regularly in a position aligned parallel to the film or at most in five layers oriented parallel to the film, specifically if the individual filaments have a fineness of 2 to 6 dtex.

Depending on the desired application more than five layers of individual filaments are possible, with increasing the number of the thickness of the carrier increases, but at the same time the strength.

As a result of the missing twisting and twisting of the parallel arrangement oriented in the longitudinal direction, the length of the individual filaments corresponds almost exactly to the running length of the carrier, and thus to the minimum of the theoretical possible length. An occurring parallel pulling force on the adhesive tape thus acts directly on each individual filament and at the same time is taken over as required by many individual filaments. This leads to a particularly effective power consumption. Due to the lack of twisting and twisting, the individual filaments also have the option of reacting to a non-parallel tensile load with an individual change in length. This leads to an optimum distribution of power over the width of the adhesive tape.

The binder is mixtures based on SBR or acrylate. Is preferably an aqueous, plasticizer-free, anionic dispersion of a carboxylated Acrylsäureestercopolymerisats (Acronal ^® 500 D).

The binder is applied in an advantageous embodiment with 10 to 30, preferably 10 to 20, most preferably 15 to 17 g / m ² to the film.

In addition to fixing the filaments, the binder can perform tasks of a functional layer.

It can act as a primer, between the carrier / filament / adhesive interface that occurs.

He can take over the tasks of a barrier layer, for example, by integrating UV absorbers the UV protection of the adhesive.

The binder may be formed as a reactive curing binder system such that it exerts no or no influence on the adhesive. At the same time, the degree of hardness of the binder can be adjusted by the reactive components. Both adjustable degrees of hardness of the binder and adjustable cohesion of the mass can be achieved by migrating crosslinkers.

• – sein viskoelastisches Verhalten
• – seiner Härte/Steifigkeit
• – der Festigkeit des Gesamtträgers, vornehmlich in z-Richtung,
• – seine optischen Eigenschaften

angepasst werden.Finally, with regard to the fibers and film used, the binder can be used to achieve an optimal bond in terms of

• - his viscoelastic behavior
• - its hardness / rigidity
• The strength of the total carrier, primarily in the z-direction,
• - its optical properties

be adjusted.

The last feature, for example, is advantageous in that the color of the adhesive tape can be easily varied. In the case of a transparent film, the entire PSA is usually dyed in order to achieve a colored adhesive tape. According to the invention, it is sufficient to equip the binder with the desired color.

The use of the binder results in non-sticky starting material that is easy to handle and store.

In the 10 such an adhesive tape is shown. The adhesive tape has a carrier, on the one side an adhesive 12 , in particular pressure-sensitive adhesive is applied. The carrier consists of a plastic film 101 and a binder layer 102 that between foil 102 and the one adhesive layer 12 is arranged.

In the binder layer 102 are a total of three layers 121 . 122 . 123 Single filaments present, with the layers 121 . 122 . 123 are aligned parallel to the film. Each individual filament is completely from the binder 102 enclosed.

The individual filaments are in the layers 121 . 122 . 123 each arranged in parallel, wherein preferably the individual filaments are almost in direct contact with each other.

Example is on the DE 10 2005 049 343 A1 in which such a filament adhesive tape is disclosed.

• • aus mono- oder biaxial orientiertem Polypropylen
• • aus mono- oder biaxial orientiertem Polyethylen oder
• • aus mono- oder biaxial orientiertem Polyester wie Polyethylenterephthalat.

According to a preferred embodiment, the film of the adhesive tape A

• • made of mono- or biaxially oriented polypropylene
• • made of mono- or biaxially oriented polyethylene or
• • Mono- or biaxially oriented polyester such as polyethylene terephthalate.

As a film material, films such as PA, PU or PVC are suitable. The films themselves may in turn consist of several individual layers, for example, layers co-extruded into film. The film may be metallized or laminated with other layers such as foams.

Preference is given to polyolefins, but also copolymers of ethylene and polar monomers such as styrene, vinyl acetate, methyl methacrylate, butyl acrylate or acrylic acid are included. It may be a homopolymer such as HDPE, LDPE, MDPE or a copolymer of ethylene with another olefin such as propene, butene, hexene or octene (for example LLDPE, VLLDE). Also suitable are polypropylenes (for example polypropylene homopolymers, polypropylene random copolymers or polypropylene block copolymers).

The film may be undrawn. According to the invention, films which are preferably monoaxially and biaxially oriented can be used as films. Deploy. Monoaxially stretched polypropylene, for example, is characterized by its very high tensile strength and low elongation in the longitudinal direction.

Particular preference is given to films based on polyesters such as polyethylene terephthalate.

The film preferably has a thickness of 10 .mu.m to 100 .mu.m, more preferably 19 to 30 .mu.m.

The film can be colored and / or transparent.

The combination of film with integrated or attached filaments preferably has an elongation of less than 10% at a load of 10 N / cm and preferably a basis weight of less than 350 g / m ² , preferably less than 200 g / m ² , completely preferably less than 150 g / m ² .

Further preferably, the film with integrated or attached filaments exhibits a maximum tensile force elongation of less than 25%, preferably less than 15%, particularly preferably less than 10%.

The adhesive tape A can also be equipped on both sides adhesive according to an alternative variant. The adhesives may differ, but they may also be identical.

It is within the scope of the invention if the carriers of the adhesive tapes A and B are identical. Thus, an embodiment in the carrier of the adhesive tape A and the carrier of the adhesive tape is preferred B have a film and extending in the longitudinal direction of the carrier filaments, more preferably, the two films may be identical. In this embodiment, moreover, it is preferred if the two adhesive tapes have the identical width.

The film carrier of the adhesive tape B may consist of a film which is a monoaxially stretched polyolefin film and which contains a mixture of an olefinic and a polar non-olefinic polymer.

In the film, the proportion of polar non-olefinic polymer in the mixture is more preferably in the range of 5 to 50% by weight, preferably 20 to 30% by weight.

To achieve high tensile strengths, high stresses at 10% elongation and high tear resistance, the stretching process conditions should be selected so that the stretch ratio is the maximum technically feasible for film. In the present invention, the stretch ratio in the longitudinal direction is preferably at least 1: 4.5, more preferably at least 1: 6.

A stretch ratio of, for example, 1: 6 indicates that a section of 6 m length of the stretched film is formed from a section of the primary film of 1 m length. Often, the draw ratio is also referred to as the quotient of the line speed before drawing and the line speed after drawing. Here the first definition is used.

• • in Längsrichtung eine Zugfestigkeit von 200 N/mm² bis 300 N/mm², vorzugsweise 220 N/mm² bis 260 N/mm², weiter vorzugsweise 240 N/mm² und/oder • in Längsrichtung eine Spannung bei 10%-Dehnung von mindestens 80 N/mm², vorzugsweise mindestens 130 N/mm², weiter vorzugsweise mindestens 150 N/mm².

In a preferred embodiment of the invention, the film has the following properties:

• A tensile strength of 200 N / mm ² to 300 N / mm ² in the longitudinal direction, preferably 220 N / mm ² to 260 N / mm ² , more preferably 240 N / mm ² and / or • a tension of 10% in the longitudinal direction Elongation of at least 80 N / mm ² , preferably at least 130 N / mm ² , more preferably at least 150 N / mm ² .

To calculate strength values, the width-related force values are divided by the thickness. In the case of a determination of the strength values on the adhesive tape, the thickness is not based on the total thickness of the adhesive tape but only on the carrier film.

As experiments with the expert Zwick known experiment setups, a tearing of the film in the transverse direction is virtually impossible. In the sample of the film to be examined, the edge is damaged by an incision in the transverse direction. Now, if train is exercised, the crack does not continue in the transverse direction, but is deflected in the longitudinal or machine direction.

The thickness of the carrier film is preferably between 15 and 200 .mu.m, more preferably between 30 and 140 .mu.m, most preferably between 50 and 100 .mu.m.

A thickness of up to 200 μm can be selected if the thickness deviations of the carton blanks or cartons to be stacked on one another by the adhesive tape are of secondary importance. Preference is given to thicknesses of a maximum of 140 μm.

The olefinic polymer is a homo- or copolymer of olefins such as ethylene, propylene or butylene. The term copolymer as used herein to mean that it includes terpolymers.

The olefinic polymer preferably contains at least 50% by weight of propylene.

Particularly suitable film raw materials are commercially available polypropylene homopolymers or polypropylene copolymers including the block (impact) and random polymers.

The melt indices of the polymers mentioned must be in the range suitable for flat film extrusion. This range should be between 0.3 and 15 g / 10 min, preferably in the range of 0.8 and 5 g / 10 min (measured at 230 ° C / 2.16 kg). The polypropylene is preferably predominantly isotactic. The flexural modulus should be at least 1000 MPa, preferably at least 1500 MPa, most preferably at least 2000 MPa.

• a) kein Olefin wie zum Beispiel Ethylen, Propylen oder Butylen als Monomer enthalten und
• b) als polare Komponente Heteroatome wie Schwefel, Stickstoff, Phosphor und vorzugsweise Sauerstoff enthalten.

By a polar non-olefinic polymer is meant all polymers which

• a) contain no olefin such as ethylene, propylene or butylene as the monomer and
• b) as a polar component heteroatoms such as sulfur, nitrogen, phosphorus and preferably oxygen.

The polar non-olefinic polymer is preferably selected from the group of polyesters, polyamides, polyurethanes, polyoxymethylene, polyarylene sulfides and polyarylene oxides. Particularly preferred are partially crystalline polymers. According to a particularly advantageous embodiment of the invention, polybutylene terephthalate and / or polyoxymethylene are chosen as the polar non-olefinic polymer.

The polar-modified polyolefin is preferably selected from the group of copolymers of olefins with vinyl esters, methacrylic acid and acrylic acid, more preferably ethylene-vinyl acetate and ethylene (meth) acrylate copolymers and their esters or from the group of graft polymers with an unsaturated organic acid, particularly preferably a maleic anhydride, methacrylic or acrylic acid grafted polyolefin is selected, wherein the proportion of polar modified polyolefin in the mixture is preferably in the range of 0.2 to 10 wt .-%.

The polymers of the film may be used in pure form or in admixture with additives such as antioxidants, sunscreen, antiblock, slip and processing aids, fillers, dyes, pigments, blowing or nucleating agents.

The film may consist of a matrix of olefinic polymer in which fibers of the polar non-olefinic polymer are embedded, which preferably have a diameter of 0.01 to 50 microns, more preferably 0.1 to 20 microns.

• • Polymere und gegebenenfalls Additive werden gemischt und in einem Extruder einer Flachfoliendüse zugeführt.
• • Der Schmelzefilm wird dann auf einer so genannten „Chillroll” kontrolliert abgekühlt.
• • Bevor die Folienbahn dem Reckwerk zugeführt wird, wird sie über temperierte Walzen auf eine geeignete Recktemperatur aufgeheizt.
• • Dann wird die Folie im Kurzspalt in Maschinenrichtung orientiert.
• • Die Trägerfolie wird durch Beschichtung oder schon vorher durch Coextrusion mit einer Klebemasse versehen.

The preferred process for producing the film or the adhesive tape A produced using the film comprises the following steps:

• Polymers and optional additives are mixed and fed to a flat film die in an extruder.
• • The melt film is then cooled in a controlled manner on a so-called "chill roll".
• • Before the film web is fed to the stretching unit, it is heated to a suitable stretching temperature using tempered rollers.
• • Then the film is oriented in the short-nip in the machine direction.
• • The carrier film is provided by coating or previously by coextrusion with an adhesive.

The film may be mono- or multi-layered, preferably it is more preferably multilayered of the type ABC, where B contains the described mixture and A and C consist entirely or predominantly of polyolefinic polymer. The coextrusion can avoid deposition during stretching of the film and problems with coating with release, primer or adhesive.

The film may be modified by lamination, embossing or radiation treatment.

The film may be provided with surface treatments. These are, for example, for bonding corona, flame, fluorine or plasma treatment or coatings of solutions or dispersions or liquid radiation-curable materials. Other possible coatings are printed coatings and anti-adhesive coatings, for example those made of cross-linked silicones, acrylates (for example Primal ^® P 376 LO), polymers of vinylidene chloride or vinyl chloride as a monomer or stearyl such as polyvinyl chromium stearate (for example Quilon ^® C) or reaction products of maleic anhydride copolymers and stearylamine.

In another embodiment of the invention, the film carrier of the adhesive tape B is preferably made of polyethylene, polypropylene, mono- or biaxially oriented polypropylene, polyester, PA, PVC or other films, more preferably MOPP.

The thickness of the carrier film of the adhesive tape B is preferably between 15 and 200 .mu.m, more preferably between 30 and 140 .mu.m, most preferably between 50 and 70 .mu.m.

A thickness of up to 200 μm can be selected if the thickness deviations of the carton blanks or cartons to be stacked on one another by the adhesive tape are of secondary importance. Preference is given to thicknesses of not more than 70 μm.

Further preferably, the film carrier has a tensile strength of 200 N / mm ² to 300 N / mm ² , more preferably 220 N / mm ² to 260 N / mm ² , most preferably 240 N / mm ² , and / or a ductility of less than 35 % on.

In order to produce the adhesive tapes A and B, all known adhesive systems can be used. In addition to natural or synthetic rubber-based adhesives, in particular polyacrylate adhesives, preferably an acrylate hot melt pressure-sensitive adhesive, can be used. Also possible are silicone adhesives.

The adhesives in the adhesive tapes A and B may be different. It is preferred that the respective same adhesive is used.

The coating thickness with adhesive is preferably in the range of 18 to 50 g / m ² , in particular 22 to 29 g / m ² , (corresponds approximately to a thickness of 18 to 50 microns, more preferably 22 to 29 microns).

The adhesive is preferably a pressure-sensitive adhesive, that is to say an adhesive which, even under relatively weak pressure, permits a permanent connection with almost all adhesive reasons and can be removed from the primer again after use essentially without residue. A PSA is permanently tacky at room temperature, so it has a sufficiently low viscosity and high tack, so that it wets the surface of the respective Klebegrunds already at low pressure. The adhesiveness of the adhesive is based on its adhesive properties and the Nederablösbarkeit on their cohesive properties.

The carriers are coated on one or both sides, preferably on one side, with pressure-sensitive adhesive from solution or dispersion or 100% (for example from the melt) or by coextrusion.

To optimize the properties, the self-adhesive composition used can be blended with one or more additives, such as tackifiers (resins), plasticizers, fillers, pigments, UV absorbers, light stabilizers, aging inhibitors, crosslinking agents, crosslinking promoters or elastomers.

Suitable elastomers for blending are, for example, EPDM or EPM rubber, polyisobutylene, butyl rubber, ethylene-vinyl acetate, hydrogenated block copolymers of dienes (for example by hydrogenation of SBR, cSBR, BAN, NBR, SBS, SIS or IR; Example known as SEPS and SEES) or acrylate copolymers such as ACM.

Tackifiers are, for example, hydrocarbon resins (for example, unsaturated C ₅ or C ₇ monomers), terpene-phenolic resins, terpene resins from raw materials such as α- or β-pinene, aromatic resins such as cumarone-indene resins or resins of styrene or α-methylstyrene such as rosin and its derivatives such as disproportionated, dimerized or esterified resins, whereby glycols, glycerol or pentaerythritol can be used. Particularly suitable are age-stable resins without olefinic double bond such as hydrogenated resins.

Suitable fillers and pigments are, for example, carbon black, titanium dioxide, calcium carbonate, zinc carbonate, zinc oxide, silicates or silicic acid.

Suitable UV absorbers, light stabilizers and aging inhibitors for the adhesives are those which are listed in this document for the stabilization of the film.

Suitable plasticizers are, for example, aliphatic, cycloaliphatic and aromatic mineral oils, di- or poly-esters of phthalic acid, trimellitic acid or adipic acid, liquid rubbers (for example nitrile or polyisoprene rubbers), liquid polymers of butene and / or isobutene, acrylic esters, polyvinyl ethers, liquid and soft resins based on the raw materials to adhesive resins, wool wax and other waxes or liquid silicones.

Crosslinking agents are, for example, phenolic resins or halogenated phenolic resins, melamine and formaldehyde resins. Suitable crosslinking promoters are, for example, maleimides, allyl esters, such as triallyl cyanurate, polyfunctional esters of acrylic and methacrylic acid.

A preferred embodiment contains a pressure sensitive adhesive of synthetic rubber, hydrocarbon resin and antioxidant.

The adhesive may be applied in the longitudinal direction in the form of a strip which has a smaller width than the carrier film of the adhesive tape. Depending on the case of use, a plurality of parallel strips of the adhesive may also be coated on the carrier film.

The free top side of the adhesive tapes A and B, which are equipped on one side with adhesive, can be provided with a release agent, also called a release.

Suitable release agents include surfactant release systems based on long chain alkyl groups such as stearylsulfosuccinates or stearylsulfosuccinamates, but also polymers which may be selected from the group consisting of polyvinyl stearyl carbamates, polyethyleneimine stearyl carbamides, chromium complexes of C ₁₄ to C ₂₈ fatty acids and stearyl copolymers such as for example in DE 28 45 541 A are described. Also suitable are release agents based on acrylic polymers with perfluorinated alkyl groups, silicones or fluorosilicone compounds, for example based on poly (dimethyl-siloxanes). Most preferably, the release layer comprises a silicone-based polymer. Particularly preferred examples of such silicone-based release polymers include polyurethane- and / or polyurea-modified silicones, preferably organopolysiloxane / polyurea / polyurethane block copolymers, more preferably those as in Example 19 of EP 1 336 683 B1 very particularly preferably anionically stabilized polyurethane- and urea-modified silicones having a silicone weight fraction of 70% and an acid number of 30 mg KOH / g. The use of polyurethane and / or urea-modified silicones causes the effect that the products according to the invention have an optimized separation behavior with optimized aging resistance and universal writability. In a preferred embodiment of the invention, the release layer comprises 10 to 20% by weight, particularly preferably 13 to 18% by weight, of the release-active constituent.

For the purposes of this invention, the general term "adhesive tape" encompasses all flat structures such as films or film sections which are expanded in two dimensions, tapes of extended length and limited width, strip sections and the like, and ultimately also diecuts or labels.

In the simplest embodiment of the invention, the adhesive tapes A and B are laminated together to form a tearing system that can be used on film, paper, cardboard or cardboard packaging.

In the following the invention will be explained in more detail with reference to several figures, without wishing to restrict the invention unnecessarily.

In the 3a It is shown that the arrangement of the adhesive tapes can be chosen arbitrarily to each other. Every tape 1 . 2 consists of a carrier 11 . 21 , on each of which an adhesive 12 . 22 is applied.

The adhesive tape B can with the adhesive-mass-free side of the film carrier 21 on the adhesive 12 of the adhesive tape A (left picture). In this case, the uncovered areas of the adhesive 12 as well as the adhesive 22 of the adhesive tape B the hold of the tear system on the selected surface safely. The adhesive tape B could also be laminated to the adhesive tape A in such a way that the adhesive composition 22 directly on the adhesive 11 of the adhesive tape A lies.

In the right picture of the 3a is shown that the adhesive 22 of the adhesive tape B on the adhesive-free side of the carrier film 11 is arranged. In this case, the adhesive provides 12 the hold of the tear-open system on the selected surface safely.

The 3b shows that the inventive concept also includes the embodiment in which the adhesive tape B is arranged on the adhesive tape A, that the carrier 11 . 21 finish flush with the edge.

Even then, the tear system of the invention works.

Preferred is the embodiment in which the adhesive tape B is applied with an offset on the adhesive tape A, that is offset in relation to the machine direction of the two adhesive tapes A, B inwardly. Thus, the two longitudinal edges L _B1 , L _{B2 of} the adhesive tape B (ie, the edges extending in the machine direction) are always perpendicular to the plane of the adhesive tape A between the two longitudinal edges L _A1 , L _{A2 of} the adhesive tape A. In the 3c this embodiment of the adhesive tape is shown as well as the mentioned projection P indicated.

In the embodiment according to 3b For example, one longitudinal edge L _B1 would be projected directly onto the longitudinal edge L _{A1 of} the adhesive tape A. Again, this is within the inventive idea.

The adhesive tapes A and B are thus arranged one above the other according to a preferred embodiment of the invention, that the two longitudinal edges L _B1 , L _{B2 of} the adhesive tape B (ie, the edges extending in the machine direction) at a vertical projection in the plane of the adhesive tape A. or between the two longitudinal edges L _A1 , L _{A2 of} the adhesive tape A or at least on one of the two longitudinal edges L _A1 , L _{A2 of} the adhesive tape A.

Particularly preferred are those in the 3a shown embodiments in which the adhesive tape B is centered on the tape A, so that there is a symmetrical structure of the Aufreißsystems.

In the 4 is shown as the tear-open system on the bottom of a carton 4 is upset, and in the 5 like the top of the box 4 looks. In the 5 they are on the bottom of the box 4 applied adhesive tapes A, B indicated by dashed lines.

Furthermore, in the 5 a preferred opening possibility of the carton 4 shown using the tear strip.

In the box 4 there is a stamping, the two handles 43 . 44 generated. The punching consists of two pairs of two V-shaped legs 41 . 42 . 41a . 42a , with both legs 41 . 42 . 41a . 42a of each pair in the potential intersection do not intersect. The thigh 41 . 42 . 41a . 42a are through the box 4 and punched through the tape A. Furthermore, the connecting line 45 , which are the endpoints of the thighs 41 . 42 . 41a . 42a connecting with each other, through the carton 4 , the adhesive tape A and the adhesive tape B punched through.

To open the box 4 becomes one of the two handles 43 . 44 , for example, the handle 43 , gripped and folded up. The punched thighs 41a . 42a produce a tear strip whose width is the distance of the ends converging leg 41a . 42a equivalent. The width of the tear strip is indicated by the parallel tear lines R _L. When pulling on the handle 43 in the direction of the arrow shown, the tear-open system separates along the lines R _L. This resulting tear strip consists of the severed cardboard 4 , the adhesive tape B and the separated tape A.

Due to the excellent properties of the described carrier, the tear strip does not taper during opening, so that the tear strip cuts through the entire carton.

Pull on the other handle 44 , also in the direction indicated by the arrow, creates a second tear strip.

More preferably, the tearing system is used to temporarily connect two packages (or other bodies), such as two cartons. This is in the 6 shown. The tape A serves to two boxes 1 . 2 link together once the adhesive tape A completely over all four sides of the boxes 1 . 2 is applied circumferentially in the edge region. The adhesive tape B, which is arranged centrally on the adhesive tape A, is located below the adhesive tape A, so that the adhesive tape B is shown in dashed lines.

The in the 5 described in detail Aufreißmöglichkeit is provided in the tear strip. To separate the two boxes is on one or both handles 43 . 44 pulled, the tear-open separates, leaving the two boxes 1 . 2 can be separated when the rupture system is completely severed.

In one variant, only the adhesive tape A is used to join two packages or other bodies together.

The adhesive tape system is preferably used as a tear strip on a cardboard 4 used that from an outer liner 46 and an inner liner 47 exists, being between the liners 46 . 47 at least one wave 48 made of cardboard, with the adhesive tape A on the inside of the outer liner 46 and the adhesive tape B on the outside of the inner liner 47 are applied, so that the adhesive tape B is arranged below the adhesive tape A. An exemplary embodiment of this use is in 7 shown.

Between the two liners 46 . 47 is a wave 48 present, with the invisible areas of the box 4 dotted are indicated.

The adhesive tape B is on the outside of the inner liner 47 glued, the further course of the adhesive tape B is indicated by dash-dotted lines.

The adhesive tape A is on the inside of the outer liner 46 glued, the further course of the adhesive tape A is indicated by dashed lines.

8th shows the tearing system according to the invention again in the in 7 shown use in a corrugated board 4 , The wave 48 runs perpendicularly out of the drawing plane. The adhesive tape B is on the outside of the inner liner 47 glued and the tape A on the inside of the outer liner 46 ,

As already in the 3c the embodiment is preferred, in which the adhesive tape B is applied with an offset relative to the adhesive tape A, that is offset inwardly with respect to the machine direction of the two adhesive tapes A, B. Thus, the two longitudinal edges L _B1 , L _{B2 of} the adhesive tape B (ie the edges extending in the machine direction) are always perpendicular to the plane of the adhesive tape A between the two longitudinal edges L _A1 , L _{A2 of} the adhesive tape A or a longitudinal edge L. _B1 , L _{B2 of} the adhesive tape B lies on one of the longitudinal edges L _A1 , L _{A2 of} the adhesive tape A.

Also the others in 3a and 3b variants of the tear system shown can be analogously transferred to this embodiment of the tear system.

Further preferably, the adhesive tape A and the adhesive tape B are applied in the form of a self-contained line on the body of the carton or in the form of several closed lines at different heights of the body.

Preferably, the line formed by the adhesive tapes lies in a plane that is parallel to the bottom of the upright carcass.

The line may also surround a corner of the body such that after tearing, a tetrahedral portion is separated from the rest of the body.

In a variant of the invention, the adhesive tapes do not form a self-contained line, but save a side wall of the carton. If the tear-open system is then removed, the last wall remains intact and can thus assume a hinge function, in particular if the wall is folded in the continuation of the line. It forms such a lid, which can be opened and closed over the hinge.

Preferably, the adhesive tape A and the adhesive tape B are applied at right angles to the shaft of the cardboard.

According to a further preferred embodiment, a stamping is present on the cardboard, which completely cuts through the adhesive tape A and preferably the cardboard underneath, and which serves as a handle for the tear-open tire when the cardboard is torn open.

The adhesive tape B is below the handle and is preferably also severed by the punched. If the handle is gripped, the tape B of the resulting tear strip is located on the underside of the handle.

The punching also determines the later width of the tear strip. For tearing open a package equipped with the adhesive tape system according to the invention, the entire width of the adhesive tape B is preferably used, while only a portion of the adhesive tape A is preferably used for the tear tape.

The width of the adhesive tape A is preferably between 10 and 50 mm, more preferably between 12 and 25 mm.

The width of the adhesive tape B is preferably between 2 and 10 mm, more preferably between 3 and 6 mm.

Preferably, the width of the adhesive tape B is chosen to be smaller than the width of the adhesive tape A, in particular in the ratio between 1: 2 and 1: 4. But it is also possible the embodiment in which the widths of the tapes A and B are identical.

The tear strip formed from the adhesive tape system according to a preferred embodiment of the invention has a width of 2 to 10 mm, more preferably between 3 and 6 mm.

The punched can be in the form of two V-shaped legs, which do not touch in the potential intersection, be executed.

Further preferably, a punching line connects the two other ends of the legs, so that the shape of a triangle results, in which the tip is missing. This triangle forms the handle on the tear strip.

In order to produce a suitable grip, the adhesive tape A must be severed in the transverse direction, ie against the stretching in any form. To determine the width of the tear strip - if the tear strip is to be arranged centrally in the adhesive tape A - two incisions in the longitudinal direction have to cut through the adhesive tape A. For example, the adhesive tape A could be pierced at two points whose connecting line is cut into the adhesive tape A (preferably this connecting line is oriented at right angles to the longitudinal edge). If the tear strip is to be formed in the edge region of the adhesive tape A, a single cut is sufficient.

In this way, the preferred embodiment of the invention results, namely that the tear strip which results inter alia from the adhesive tape A has a smaller width than the adhesive tape A.

The handle does not necessarily have to be punched. It is also possible to create the handle using a knife by at least partially severing the tape A transversely and inserting two substantially machine direction notches into the tape A at the parting line, the spacing of the notches being the width of the tear strip. The notches and the incision define a grip area that forms the beginning of the tear strip. Make sure that the adhesive tape B is also severed at the same time.

For example, the adhesive tape system described is glued to the corrugator during corrugated board production. In further steps, the sheet created after the corrugated cardboard plant is further made into a box. On the box at least one punched is introduced, which makes it possible to detach a handle from the adhesive tape system for later opening the package. At this handle is pulled and the forming handle strip separates during the opening process located directly above him Papplage from the box.

Furthermore, the invention includes a carton consisting of an outer liner and an inner liner, wherein between the liners at least one shaft of cardboard is arranged, equipped with an adhesive tape system according to the invention, wherein the adhesive tape A on the inside of the outer liner and the Adhesive tape B are applied to the outside of the inner liner, so that the adhesive tape B is disposed below the adhesive tape A.

The adhesive tape A shows, in particular with a synthetic rubber-based adhesive which has sufficient bond strength and high tack, good adhesion to various paper substrates.

Due to the special carrier, cracks surprisingly propagate in this straight and parallel to the machine direction (x-direction) starting from the punching. Next surprisingly, the carrier tears not only transverse to the direction of stretching not further, but supports the tearing of the film in the longitudinal direction reliably. That is, no tapering takes place in y (in the transverse direction of the strip) or else in the z direction (direction that defines the direction of the carrier). As a result, the tearing is only possible in the x-direction (longitudinal or machine direction). Furthermore, the continuous tearing in the x direction is easy to do manually in addition to tearing the corrugated board.

Optionally, a slight taper or broadening occurs in the transverse direction, preferably not more than 5 parts per thousand by length.

The necessary strength can be achieved with significantly lower material thicknesses, so that the total thickness of adhesive tape can be reduced by up to 50% compared to the previously described Adalis system. This leads to less wear on the printing, improved stability in stacking the boxes, and longer run lengths of the adhesive tape reels possible, that is, larger production campaigns can be safely driven without interrupting the process.

The adhesive tape B also shows, in particular with a synthetic rubber-based adhesive, which has a sufficient bond strength and a high tack, good adhesion to various paper substrates.

Furthermore, the film carrier has a high tensile strength, because the tape must absorb the main load when opening the box and must not tear. Furthermore, the carrier shows a low elongation, in particular a ductility of less than 35%, because otherwise it will stretch too much under the given loads.

The invention will be explained in more detail with reference to some examples, without wishing to limit the invention in any way.

Examples

test methods

The measurements are carried out at a test climate of 23 ± 1 ° C and 50 ± 5% rel. Humidity carried out.

tensile elongation

The tensile elongation behavior of the adhesive tape is reflected on test specimens (rectangular, 100 mm long and 15 mm wide test strips) DIN EN 14410: 2003 527-3 / 2/300 with a test speed of 300 mm / min, a clamping length of 100 mm and a pre-load of 0.3 N / cm determined, with patterns are cut to determine the data with sharp blades.

The tensile elongation behavior is tested in the machine direction (MD, direction of travel) unless otherwise specified. The force (tensile strength) is expressed in N / strip width or N7mm ² and the elongation at break in%. The test results, in particular the elongation at break (elongation at break), are to be statistically verified by five measurements.

Peel strength (bond strength, KK)

To measure the bond strengths, 19 mm wide test strips were bubble-free affixed to a finely ground (240 grit FEPA grit paper) stainless steel steel plate and pressed with a rubber-wound 2 kg roller at a speed of 10 ml / min. The steel plate and the projecting end of the adhesive tape were then tensioned in the ends of a tensile testing machine to give a peel angle of 180 °. The adhesive tape was peeled from the steel plate at a speed of 300 mm / min. The adhesive strength is given in N / cm.

Shear Life (Holding Power, HP)

Shear life indicates the bond strength for a loading force acting parallel to the bonded tape. It is the time taken to completely shearing a loaded tape from a steel plate.

To determine the HP values, a 19 mm wide test strip is glued onto a pretreated steel plate to form a bond area of 19 × 20 mm ² . A 1 kg weight is hung on the protruding end of the adhesive tape with the aid of a clamp, so that a vertical tensile force of 5.15 N per 1 cm belt width is transmitted.

The unit of shear time is minutes. If there is a ">" sign in front of the values, this means that the measurements were aborted after this time, as no scissors had yet been detected.

thickness

It's going to be DIN 53370 certainly.

raw materials

• Dow 7C06: PP block copolymer, MFI 1.5 g / 10 min, non-nucleated, flexural modulus 1280 MPa (Dow Chemical)
• Bormod HD 905 CF: PP homopolymer, MFI 6 g / 10 min, flexural modulus 2150 MPa, contains an α-nucleating agent (borealis)
• Dowlex 2032: PE-LLD, MFI 2 g / 10 min (Dow Chemical)
• Styron 457: PS-HI, MFI 3 g / 10 min, flexural modulus 2200 MPa (Dow Chemical)
• EVAL G156B: EVAL ethylene content 48 mol%, MFI 6.4 g / 10 min, flexural modulus 2800 MPa (EVAL Europe)
• Licocene PP MA 7452 GR TP: PP-g-MA, maleic anhydride-grafted metallocene polypropylene wax (Clariant)
• Hostaform C9021 nature: POM, MFI 8 g / 10 min, flexural modulus 2800 MPa (Ticona)
• Celanex 2002-2 nature: PBT, MFI 20, flexural modulus 2500 MPa (Ticona)

In the following, advantageous embodiments of the adhesive tape according to the invention will be described by way of examples, without wishing to unnecessarily limit the invention.

example 1

The adhesive tape A is 25 mm wide and consists of a 19 .mu.m carrier sheet of polyethylene terephthalate, which is reinforced with a Weft inserted warp knit (WIWK). The WIWK points
7 threads / cm 34 tex polyester thread as reinforcement (warp direction = warp thread)
2 threads / cm 34 tex polyester thread (Weft direction = weft thread)
on.

The WIWK is bonded to the film by a laminating adhesive with the adhesive applied at 10 g / m ² .

The film is coated on top with 0.07 g / m ² carbamate release and dried.

The adhesive is made from 42% by weight of SIS elastomer, 20% by weight of pentaerythritol ester of hydrogenated rosin, 37% by weight of a C ₅ hydrocarbon resin having an R & B value of 85 ° C. and 1% by weight Irganox antioxidant ^® 1010 melt-mixed and applied at 150 ° C with a nozzle on the underside of the film, and with 50 g / m ² .

The result is a KK on steel of 6 N / cm and a shear strength of greater than 3000 min.

The elongation at break of the adhesive tape is below 40%, the tensile strength above 80 N / cm.

The film carrier of the adhesive tape B is produced as follows:
The raw materials are compounded and granulated. The granules are fed to a single-screw extrusion plant. The film carrier for the adhesive tape B is produced on this single-flute single-flute extrusion die with a flexible die lip, followed by a chill roll station and a single-stage short-gap stretching line. Dow 7C06, Celanex 2002-2 natural and Licocene PP MA 7452 GR TP are mixed and extruded in a ratio of 15: 4: 1. The nozzle temperature is 230 ° C. Chillroll temperatures and stretch roll temperatures are adjusted to maximize the crystallinity of the film before and after the stretching operation. The stretch ratio is 1: 5. Film properties: Tensile strength / N / mm ² 240 Width (mm 25 Elongation at break /% 30 Thickness / micron 60

The film is coated on top with 0.05 g / m ² carbamate release and dried.

The adhesive is made from 42% by weight of SIS elastomer, 20% by weight of pentaerythritol ester of hydrogenated rosin, 37% by weight of a C ₅ hydrocarbon resin having an R & B value of 85 ° C. and 1% by weight Irganox antioxidant ^® 1010 melt-mixed and applied at 150 ° C with a nozzle on the underside of the film, and with 25 g / m ² .

The result is a KK on steel of 6 N / cm and a shear strength of greater than 3000 min.

The adhesive tapes A and B are applied as described in the invention on a cardboard box from a 2.30 double shaft according to RAL-GZ 492 (GERMAN INSTITUTE FOR GUARANTEE AND LABELING E.V.).

After tearing open a clean edge and only a slight impairment of the outer liner.

Example 2

The carrier for the adhesive tape A from Example 1 is used.

The film carrier of the adhesive tape B is a film of MOPP. Film properties: Tensile strength / N / mm ² 180 Width (mm 4 Elongation at break /% 27 Thickness / micron 60

The film is coated on top with 0.05 g / m ² silicone release and dried. The adhesive is made from 42% by weight of SIS elastomer, 20% by weight of pentaerythritol ester of hydrogenated rosin, 37% by weight of a C ₅ hydrocarbon resin having an R & B value of 85 ° C. and 1% by weight Irganox antioxidant ^® 1010 melt-mixed and applied at 150 ° C with a nozzle on the underside of the film, and with 25 g / m ² .

The result is a KK on steel of 6 N / cm and a shear strength of greater than 3000 min.

The adhesive tapes A and B are applied as described in the invention on a cardboard box from a 2.30 double shaft according to RAL-GZ 492 (GERMAN INSTITUTE FOR GUARANTEE AND LABELING E.V.).

After tearing open a clean edge and only a slight impairment of the outer liner.

Example 3

The carrier for the adhesive tape A from Example 1 is used.

It is the of the film carrier for the adhesive tape B used in Example 1, but with a width of 15 mm. Film properties: Tensile strength / N / mm ² 240 Width (mm 15 Elongation at break /% 30 Thickness / micron 60

The adhesive tapes A and B are applied as described in the invention on a cardboard box from a 1.40 single shaft according to RAL-GZ 492 (GERMAN INSTITUTE OF GUARANTEE AND IDENTIFICATION E.V.).

After tearing open a clean edge and only a slight impairment of the outer liner.

Example 4

The adhesive tape A is 25 mm wide and consists of a 19 .mu.m carrier sheet of polyethylene terephthalate, which is reinforced with a Weft inserted warp knit (WIWK). The WIWK points
7 threads / cm 34 tex polyester thread as reinforcement (warp direction = warp thread)
2 threads / cm 34 tex polyester thread (Weft direction = weft thread)
on.

The WIWK is bonded to the film by a laminating adhesive with the adhesive applied at 10 g / m ² .

The first adhesive is composed of 42% by weight of SIS elastomer, 20% by weight of pentaerythritol ester of hydrogenated rosin, 37% by weight of a C ₅ hydrocarbon resin having an R & B value of 85 ° C. and 1% by weight of antioxidant Irganox ^® 1010 melt blended and applied at 150 ° C with a nozzle to the film base, with 50 g / m ^2.

A second adhesive, identical to the first, is also melt blended and applied at 150 ° C with a die to the top of the film at 50 g / m ² .

The result is a KK on steel of 6 N / cm and a shear strength of greater than 3000 min (top and bottom).

The elongation at break of the adhesive tape is below 40%, the tensile strength above 80 N / cm.

The film carrier of the adhesive tape B is produced as follows:
The raw materials are compounded and granulated. The granules are fed to a single-screw extrusion plant. The film carrier for the adhesive tape B is produced on this single-flute single-flute extrusion die with a flexible die lip, followed by a chill roll station and a single-stage short-gap stretching line. Dow 7C06, Celanex 2002-2 natural and Licocene PP MA 7452 GR TP are mixed and extruded in a ratio of 15: 4: 1. The nozzle temperature is 230 ° C. Chillroll temperatures and stretch roll temperatures are adjusted to maximize the crystallinity of the film before and after the stretching operation. The stretch ratio is 1: 5. Film properties: Tensile strength / N / mm ² 240 Width (mm 25 Elongation at break /% 30 Thickness / micron 60

The film is coated on top with 0.05 g / m ² carbamate release and dried.

The adhesive is made from 42% by weight of SIS elastomer, 20% by weight of pentaerythritol ester of hydrogenated rosin, 37% by weight of a C ₅ hydrocarbon resin having an R & B value of 85 ° C. and 1% by weight Irganox antioxidant ^® 1010 melt-mixed and applied at 150 ° C with a nozzle on the underside of the film, and with 25 g / m ² .

The result is a KK on steel of 6 N / cm and a shear strength of greater than 3000 min.

The adhesive tapes A and B are applied as described in the invention on a cardboard box from a 2.30 double shaft according to RAL-GZ 492 (GERMAN INSTITUTE FOR GUARANTEE AND LABELING E.V.).

After tearing open a clean edge and only a slight impairment of the outer liner.

LIST OF REFERENCE NUMBERS

30

dryer

31

wave

32

outer liner

33

inner liner

34

Band B

35

Volume A

36

liner slitting

37

Load in Z direction

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 3,187,982 A [0003]
• US 3,311,032 A [0003]
• CA 749198 A [0003]
• DE 2104817 A [0004]
• US 3,088,848 A [0004]
• US 3,482,683 A [0004]
• US 2956904 A [0004]
• DE 4338524 A1 [0005]
• EP 0269967 A1 [0015]
• DE 102006023935 A1 [0047]
• EP 1818437 A1 [0057]
• DE 102005049343 A1 [0086]
• DE 2845541 A [0139]
• EP 1336683 B1 [0139]

Cited non-patent literature

• "Packaging Review" of February 1973, page 57 [0004]
• DIN EN 14410: 2003 527-3 / 2/300 [0195]
• DIN 53370 [0201]

Claims (23)

Adhesive tape system, in particular for opening cardboard boxes, comprising an adhesive tape A equipped with an adhesive coating on at least one side with a carrier, wherein the carrier has a film and filaments extending in the longitudinal direction of the carrier, and an adhesive tape B equipped with a film carrier at least on one side with an adhesive coating, wherein the adhesive tapes A and B are arranged one above the other. Adhesive tape system according to claim 1, characterized in that the filaments are laminated to the film. Adhesive tape system according to claim 1 or 2, characterized in that the filaments are endless filaments. Adhesive tape system according to at least one of claims 1 to 3, characterized in that the filaments are arranged in a parallel aligned position or at most in three parallel aligned layers. Adhesive tape system according to at least one of the preceding claims, characterized in that the filaments of glass, carbon (carbon), combinations of two types of fibers, aramid fibers, polyamide and / or drawn polymer fibers such as polyester fibers (such as polyethylene terephthalate), polypropylene fibers, polyethylene fibers consist. Adhesive tape system according to at least one of the preceding claims, characterized in that there are between 1 and 30 filaments per centimeter width in the carrier, in particular between 1 and 5, more particularly between 1 and 3. Adhesive tape system according to at least one of the preceding claims, characterized in that the number of filaments is at least 3, preferably 3 to 30, more preferably 3 to 20, most preferably 3 to 10 filaments. Adhesive tape system according to at least one of the preceding claims, characterized in that, in addition to the filaments running in the longitudinal direction (machine direction), there are additionally such filaments in the support which run in the transverse direction and / or in an oblique direction. Adhesive tape system according to at least one of the preceding claims, characterized in that the film is reinforced by an open Filamentgelege or an open filament fabric. Adhesive tape system according to at least one of the preceding claims, characterized in that the carrier consists of a film and a binder layer which is disposed between the film of the carrier and the adhesive layer, wherein in the binder layer untwisted and ungetgelte single filaments are inserted in the longitudinal direction, which is completely from the Binder layer are enclosed. Adhesive tape system according to at least one of the preceding claims, characterized in that the film of the adhesive tape A consists of • mono- or biaxially oriented polypropylene • mono- or biaxially oriented polyethylene or Mono- or biaxially oriented polyester such as polyethylene terephthalate Adhesive tape system according to at least one of the preceding claims, characterized in that the film of the adhesive tape B is a polyolefin film stretched monoaxially in the longitudinal direction and the film contains a mixture of an olefinic and a polar non-olefinic polymer. Adhesive tape system according to at least one of the preceding claims, characterized in that in the film of the adhesive tape B, the proportion of polar non-olefinic polymer in the mixture of the film of the adhesive tape in the range of 5 to 50 wt .-%. Adhesive tape system according to at least one of the preceding claims, characterized in that the film carrier of the adhesive tape B is a film of polyethylene, polypropylene, mono- or biaxially oriented polypropylene, polyester, PA, PVC, preferably of MOPP. Adhesive tape system according to at least one of the preceding claims, characterized in that the film carrier of the adhesive tape B has a tensile strength of 200 N / mm ² to 300 N / mm ² , preferably 220 N / mm ² to 260 N / mm ² , more preferably 240 N / mm ² and / or has a ductility of less than 35%. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard consisting of an outer liner and an inner liner, wherein between the liners at least one shaft of cardboard is arranged, wherein the adhesive tape A on the inside of the outer liner and the Adhesive tape B are applied to the outside of the inner liner, so that the adhesive tape B is disposed below the adhesive tape A. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard, characterized in that the adhesive tape A and the adhesive tape B are applied in the form of a self-contained line on the body of the carton or in the form of several closed lines at different heights of body. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard, the adhesive tape A and the adhesive tape B are applied at right angles to the shaft of the cardboard. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard, characterized in that on the cardboard a punching is present, which completely cuts through the adhesive tape A and preferably the cardboard underneath and as a handle for the Aufreißtreifen when tearing the cardboard serves. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard, characterized in that the punched in the form of two V-shaped legs, which do not touch in the potential intersection, is executed. Use of the adhesive tape system according to claim 19 as a tear strip on a cardboard, characterized in that a punching line connects the other two ends of the legs, so that the shape of a triangle results, in which the tip is missing. Use of the adhesive tape system according to at least one of the preceding claims as a tear strip on a cardboard, characterized in that the tearing strip resulting from the adhesive tape A and the adhesive tape B has a smaller width than the adhesive tape A. Cardboard, which consists of an outer liner and an inner liner, wherein between the liners at least one shaft of cardboard is arranged, equipped with an adhesive tape system according to the invention, wherein the adhesive tape A on the inside of the outer liner and the adhesive tape B on the outside of the inner Liners are applied, so that the adhesive tape B is disposed below the adhesive tape A.

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